CAN/CSA-ISO/IEC 8802-5-97 (R2001)

The international community has decided to make this standard available only in the English language version. It has been adopted as a National Standard of Canada on this basis. This National Standard of Canada is equivalent to International Standard ISO/IEC 8802-5:1995 and ANSI/IEEE Std 802.5-1995. 1.1 Scope For the purpose of compatible interconnection of data processing equipment via a local area network (LAN) using the token ring access method, this part of ISO/IEC 8802. a) Provides a general description of the token ring local area network (LAN) architecture (clause 2); b) Defines the frame format, including the delimiters, address fields, information field, and frame-check sequence (FCS). Defines the Medium Access Control (MAC) frames, timers, and error counters (clause 3); c) Defines the MAC protocols including finite-state machines and state tables (clause 4); d) Defines the system level Physical layer (PHY) signaling specifications that are specific to a ring station (clause 5); e) Defines the managed objects necessary to manage the service and protocol elements that are involved in the management of a token ring station (clause 6); f) Defines the PHY station attachment specification for 4 and 16 Mbit/s operation. This includes the transmitter, receiver, medium interface connector, and transmission channel for both shielded twisted pair (STP) and unshielded twisted pair (UTP) medium (clause 7); g) Defines the concentrator, incorporating multiple trunk coupling units (TCUc), for the attachment of a group of stations to the ring (clause 8); h) Includes the protocol implementation conformance statement (PICS) proforma in compliance with the relevant requirements, and in accordance with the relevant guidance, given in ISO/IEc 9646-2:1994¹ (annex A); i) Includes channel design examples and formulas for calculating cabling and concentrator system configurations (annex B); j) Describes jitter components and provides an example of jitter buildup using a phase lock loop recovery circuit (annex C); k) Provides informative transmitter filter design example (annex D); l) Provides recommended guidelines for safety and operating environments (annex E); m) Illustrates the MAC finite-state machines in a notation similar to that used in ISO/IEC 8802-5:1992 (annex F); n) Describes major improvements between this standard and the previous edition, ISO/IEC 8802-5:1992 (annex G); o) Provides a sample algorithm for the parsing of MAC frames (annex H); p) Provides recommendations for the use of token ring access priorities to support multimedia traffic (annex I). A particular emphasis of this standard is to specify the externally visible characteristics needed for interconnection compatibility, while avoiding unnecessary constraints upon and changes to internal design and implementation of the heterogeneous processing equipment to be interconnected. The applications environment for the LAN is intended to be commercial and light industrial. The use of token ring LANs in home and heavy industrial environments, while not precluded, has not been considered in the development of this standard. This standard, the Second Edition of part of ISO/IEC 8802, provides greater specificity and improved clarity to the First Edition (1992-06-12) to ensure interoperability of the various components in the token ring network. The intent of this standard is to maintain interoperability with stations designed to this specification a